The present invention relates to a kneading device and a ropesizer which are suitable for producing confectionery such as a soft candy. In particular, the present invention relates to a kneading device and a ropesizer which make possible a continuous production of such confectionery.
Recently, soft candies are being marketed that have superior softness when initially chewed and do not adhere to the teeth. Such soft candies may be produced by, for instance, the following process:
a first step in which a saccharide, water, vegetable oil, and emulsifier are mixed and emulsified to prepare a soft candy base raw material liquid;
a second step in which the soft candy base raw material liquid is boiled down to obtain a high viscosity raw material which is used as a soft candy base;
a third step in which after mixing and boiling down sucrose, water, and glucose syrup, the mixture is cooled and crystals are precipitated to obtain a fine sucrose crystal composition;
a fourth step in which a low viscosity raw material including the fine sucrose crystal composition obtained in the third step is added to and mixed with the high viscosity raw material (the soft candy base) obtained in the second step to obtain a high viscosity mixture (i.e., a raw material mixture);
a fifth step in which saccharide, water, and foaming protein such as gelatin are mixed and whipped to obtain a frappe;
a sixth step in which a secondary raw material such as the frappe obtained in the fifth step is added to and mixed with the mixture (the raw material mixture), which is obtained in the fourth step and is used as a primary raw material, to obtain a soft candy composition in which a large amount of air is included to give a characteristic of a soft candy; and,
a seventh step in which two kinds of the soft candy compositions having different flavor are prepared in the sixth step, and they are formed into a product by wrapping one of the soft candy compositions with the other one of the soft candy compositions.
In the production process mentioned above, since it is difficult to sufficiently carry out a mixing (mulling) process and, at the same time, continuously convey the resultant mixture, especially in the fourth step in which the low viscosity raw material including the fine sucrose crystal composition is added to and mixed with the high viscosity raw material (the soft candy base) to obtain the high viscosity mixture (the raw material mixture), a batch type production process is conventionally adopted and a continuous production process is not employed.
Also, for the same reason as above, a batch type production process is adapted for the sixth step in which the secondary raw material such as the frappe is added to and mixed with the mixture (the raw material mixture) to obtain a soft candy composition, and a continuous production process is not utilized.
Moreover, in the seventh step in which one of the materials is wrapped up by the other to be formed into a product, a method is adopted in which an extrusion instrument, for instance, an extruder, is used and the nozzle thereof is made duplex to form the product, or in which the product is prepared by hand.
However, since the raw material to be mixed (mulled) deteriorates over time and the physical properties of the products differ at the initial production stage and at the final production stage if the batch type production process is employed for the above-mentioned fourth or sixth step, it becomes necessary to adjust the conditions such as temperature or time in the subsequent steps in order to eliminate the effect of the difference over time. Accordingly, production control becomes complicated, and this is one of the factors which reduces productivity.
In order to solve the above problems, although attempts have been made and experiments have been conducted to prepare a product by using a kneading device such as a single axial or twin axial extruder or onrator, a desired kneaded material could not be obtained due to such factors as heat generated during the kneading process. That is, the characteristics of soft candy which has superior softness when initially chewed and which is resistant to adhering to the teeth is obtained mainly in the above-mentioned sixth step, and in the fourth step in which a large quantity of air is incorporated into the mixture. However, in the above-mentioned kneading device, the amount of air incorporated into the mixture becomes insufficient due to such factors as heat generated in the mixing process, and as a result, a mixture having desired properties cannot be obtained.
Also, as for the above-mentioned seventh step, if the method is employed in which an extrusion instrument such as an extruder is used and the nozzle thereof is made duplex to form the product, there are certain limits in the working conditions: for instance, if a raw material is used whose content of fats and oils is, for example, 8% or more, it generates oil stains. Moreover, if the method in which the product is manually prepared is employed, the wrapping amount of the product, and hence, the quality of the product may differ from one product to another. Accordingly, it is not suitable for use in a continuous production process.
The present invention takes into consideration the above-mentioned circumstances, with the object of providing a kneading device which makes possible the introduction of air into the mixture and the continuous conveyance of the mixture while a mixing process is being carried out, as well as providing a ropesizer which is capable of continuously forming a product by wrapping one of the raw material with the other which are continuously conveyed from the above-mentioned kneading device.
The kneading device in one embodiment kneads a raw material of high viscosity and a raw material of low viscosity and continuously delivers a raw material mixture obtained, including: a casing; a pair of screw shafts disposed parallel to each other in the casing; and, a driving unit for rotating the screw shafts, wherein a helical portion is formed at one end of the pair of screw shafts so that the raw material is conveyed from one end of each of the pair of screw shafts to the other end, and a plurality of mixing pins is provided with the other end side of the screw shaft with regard to the helical portion in the circumferential direction of the screw shaft.
In another embodiment, each member of the pair of screw shafts is configured so as to rotate inwardly from top to bottom.
In another embodiment, a mixing pin is provided at the inside of the casing.
In another embodiment, the plurality of mixing pins provided with the pair of screw shafts is arranged at a height so that they overlap with each other between the pair of screw shafts in such a manner that they do not interfere with each other.
In another embodiment, an overlapping portion of the mixing pins between the pair of screw shafts is equal to or less than a half of the height of the mixing pin.
In another embodiment, the plurality of mixing pins are formed in a flat plate shape and are obliquely disposed with respect to a rotation axis of the screw shaft so that the surfaces of the mixing pins facing the other end of the screw shaft face the rotation direction of the screw shaft.
In another embodiment, an introduction opening for the raw material having high viscosity and an introduction opening for the raw material having low viscosity towards the pair of screw shafts are provided separately.
In another embodiment, an outlet for discharging the raw material mixture is provided with the casing at a position below the other end of the screw shaft, and a wiping plate for wiping off the raw material mixture, which is conveyed by the screw shafts, to the outlet is provided with the casing at a position corresponding to the other end of the screw shafts.
In another embodiment, a cover for sealing the inside of the casing is provided with the casing so that 5-50% of the inside volume of the sealed space is empty.
In another embodiment, a kneading device kneads a main raw material of high viscosity and a secondary raw material of liquid or powder and continuously delivers a kneaded raw material obtained, including: a casing having an opened upper portion; a pair of mixing blades disposed parallel to each other in the casing; and, a driving unit for rotating the mixing blades, wherein each of the pair of mixing blades comprises a unit blade of a U-shape continuously attached in a wavy shape, and the pair of the mixing blades rotate with their rotational phases shifted so that they do not interfere with each other.
In another embodiment, each of the pair of mixing blades is configured so as to rotate inwardly from top to bottom.
In another embodiment, an inclined portion facing the other end of the mixing blades is provided with the surface of the mixing blades facing the rotation direction thereof so that the raw materials may be conveyed from one end of the mixing blades to the other end thereof.
In another embodiment, an inclination member is provided for changing the angle of inclination of the inclined portion which is detachably attached to the inclined portion.
In another embodiment, a ropesizer includes a sheet forming unit for elongating a first raw material into a sheet shape; a delivering unit which applies a second raw material onto the first raw material, which is elongated in sheet shape and conveyed by the sheet forming unit, so as to be in a strand form; and, a wrap unit to wrap the sheet shape first raw material, while the sheet shape first raw material is being conveyed, so as to wrap the second raw material, which is applied as a strand form, in the first raw material.
In another embodiment, the ropesizer includes an elongation unit which elongates an intermediate product having a large diameter, which is obtained by wrapping the second raw material in the first raw material by the wrap unit, and produces an intermediate product having a smaller diameter.
In another embodiment, the delivering unit comprises a plurality of cone members arranged with their cone points pointing downwardly so as to be a side surface of a cone, each of the cone members rotating in the same direction around the central axis thereof as a rotation axis as well as rotating in the circumferential direction of the side surface of the cone around the central axis of the cone as a rotation axis so that the second raw material supplied to the inside of the cone is discharged from the bottom portion thereof in a strand form.
In another embodiment, the elongation unit is provided with a conveyance passage which conveys the intermediate product having a smaller diameter in a free state without elongating the intermediate product in order to achieve stress relaxation in the intermediate product being elongated.